Variable Emittance Window

Abstract

A smart window comprising a transparent substrate, a transparent low emittance layer on the transparent substrate, a variable emittance material layer on the substrate or transparent low emittance layer, and a protection material layer on the variable emittance material layer.

What we claim is: 
     
         1 . A variable emittance window comprising:
 a transparent substrate;   a transparent low emittance layer on the transparent substrate;   a variable emittance material layer on the substrate or transparent low emittance layer; and   a protection material layer on the variable emittance material layer.   
     
     
         2 . The variable emittance window of  claim 1  further including:
 a transparent strain optimizing material layer on the variable emittance material layer to optimize strain in the variable emittance layer wherein the variable emittance material layer has a selected phase transition temperature. 
 
     
     
         3 . The variable emittance window of  claim 1  further including:
 a hydrophobic material layer on an outer surface of the variable emittance window. 
 
     
     
         4 . The variable emittance window of  claim 1  wherein the variable emittance material layer is an atomic layer deposition material layer. 
     
     
         5 . The variable emittance window of  claim 1  wherein the variable emittance material layer is an atomic layer deposition vanadium oxide material layer. 
     
     
         6 . The variable emittance window of  claim 1  wherein the variable emittance material layer is a two-step variable emittance layer. 
     
     
         7 . The variable emittance window of  claim 2  where in the transparent low emittance layer is a transparent conductive oxide layer. 
     
     
         8 . The variable emittance window of  claim 2  further including:
 an antireflection material layer on the protection material layer. 
 
     
     
         9 . The variable emittance window of  claim 2  wherein the transparent strain optimizing material layer on the variable emittance material layer to optimize the strain in the variable emittance layer is an atomic layer deposition material layer. 
     
     
         10 . The variable emittance window of  claim 8  wherein the antireflection material layer is TiO 2 . 
     
     
         11 . The variable emittance window of  claim 9  wherein the transparent transparent strain optimizing material layer on the variable emittance material layer is fluorine doped tin oxide or antimony oxide. 
     
     
         12 . The variable emittance window of  claim 4  wherein the substrate is flexible. 
     
     
         13 . A variable emittance window comprising:
 a transparent substrate;   a transparent low emittance material layer comprising a metal on the substrate;   a variable emittance material layer on the transparent low emittance material layer;   a protection material layer on the variable emittance material layer; and   an antireflection material layer on the protection material layer.   
     
     
         14 . The variable emittance window of  claim 13  wherein the transparent low emittance material layer comprising a metal comprises one selected from the group consisting of atomic layer deposited platinum metal, atomic layer deposited silver metal, and atomic layer deposited ruthenium metal. 
     
     
         15 . The variable emittance window of  claim 14  wherein the variable emittance material layer comprises atomic layer deposited vanadium oxide. 
     
     
         16 . A method of making a variable emittance window comprising:
 providing a transparent substrate;   applying a transparent low emittance material layer to the substrate;   applying a variable emittance material layer onto the transparent low emittance material layer;   applying a protection material layer onto the variable emittance material layer; and   applying an antireflection material layer onto the protection material layer.   
     
     
         17 . The method of making a variable emittance window of  claim 16  further including the step of:
 annealing to form a variable emittance layer. 
 
     
     
         18 . The method of making a variable emittance window of  claim 17  wherein the annealing is laser annealing. 
     
     
         19 . A method of making a variable emittance window comprising:
 providing a metal foil substrate;   applying an antireflection material layer onto the metal foil substrate;   applying a protection material layer onto the antireflection material layer;   applying a variable emittance material layer onto the protection material layer;   annealing to form a two-step variable emittance layer;   applying a transparent low emittance material layer to the two-step variable emittance layer;   adhering a transparent substrate to the transparent low emittance material layer; and   removing the metal foil substrate.   
     
     
         20 . A method of making a variable emittance window comprising:
 providing a transition metal foil substrate;   growing a graphene material layer on the metal foil substrate;   functionalizing the surface of the graphene material layer;   applying an antireflection material layer onto the metal foil substrate;   applying a protection material layer onto the antireflection material layer;   applying a variable emittance material layer onto the protection material layer;   annealing to form a two-step variable emittance layer;   applying a transparent low emittance material layer to the two-step variable emittance layer;   applying a first flexible transparent substrate to the transparent low emittance material layer; and   peeling the first flexible transparent substrate, the transparent low emittance material layer, the two-step variable emittance layer, the protection material layer, the antireflection material layer, and the functionalized graphene material layer from the surface of the copper.   
     
     
         21 . The method of making the variable emittance window of  claim 20 , wherein a second transparent substrate is adhered to the exposed surface of the first flexible transparent substrate or to the graphene material layer. 
     
     
         22 . The method of making the variable emittance window of  claim 20  wherein the step of applying a variable emittance material layer comprises an atomic layer deposition process and wherein the step of applying occurs at a temperature at or below 115° C. 
     
     
         23 . A method of making a variable emittance window comprising:
 providing a transition metal foil substrate;   growing a graphene material layer on the transition metal foil substrate;   functionalizing a surface of the graphene material layer;   applying a transparent low emittance material layer to the graphene material layer;   applying a variable emittance material layer onto the transparent low emittance material layer;   annealing to form a two-step variable emittance film;   applying a protection material layer onto the variable emittance material film; and   applying an antireflection material layer onto the protection material layer;   adhering a polymer tape onto the antireflection material layer;   peeling the polymer tape, the antireflection material layer, the protection material layer, the variable emittance material layer, the transparent low emittance material layer, and the graphene material layer from the surface of the metal foil substrate and transferring to a transparent substrate; and   releasing the polymer tape.